MODULE t1;
IMPORT Out, In, Math;
VAR x1 : INTEGER;
PROCEDURE x(VAR x:ARRAY OF CHAR);
BEGIN
  x
END x;

END t1.

(* 
java.lang.ClassCastException: org.antlr.runtime.tree.CommonTree cannot be cast to ru.msu.cmc.sp.oberon2.InterAST
	at ru.msu.cmc.sp.oberon2.Types.call_stat(Types.java:389)
	at ru.msu.cmc.sp.oberon2.Types.topdown(Types.java:240)
	at ru.msu.cmc.sp.oberon2.Types.topdown(Types.java:1)
	at org.antlr.runtime.tree.TreeRewriter$2.rule(TreeRewriter.java:108)
	at org.antlr.runtime.tree.TreeRewriter.applyOnce(TreeRewriter.java:61)
	at org.antlr.runtime.tree.TreeRewriter$1.pre(TreeRewriter.java:92)
	at org.antlr.runtime.tree.TreeVisitor.visit(TreeVisitor.java:56)
	at org.antlr.runtime.tree.TreeVisitor.visit(TreeVisitor.java:60)
	at org.antlr.runtime.tree.TreeVisitor.visit(TreeVisitor.java:60)
	at org.antlr.runtime.tree.TreeRewriter.downup(TreeRewriter.java:95)
	at org.antlr.runtime.tree.TreeRewriter.downup(TreeRewriter.java:86)
	at ru.msu.cmc.sp.oberon2.Oberon2.analysis(Oberon2.java:29)
	at ru.msu.cmc.sp.oberon2.Oberon2.main(Oberon2.java:47)
*)